Golf club sole configuration

ABSTRACT

A golf club or set of golf clubs include a sole having four surfaces: a bottom crescent surface, a positive bounce surface, a heel surface and a toe surface. The bottom crescent surface has a generally straight back boundary approximate the trailing edge and a curved front boundary. Moreover, the bottom crescent surface is substantially flat with the ground when the club addressed by the player.

TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates generally to golf clubs and, moreparticularly, to the sole of iron-type golf clubs.

BACKGROUND OF THE INVENTION

[0002] Iron type golf clubs generally include a front face, a top lineand a sole. The front face interfaces with and strikes the golf ball. Aplurality of score lines or grooves are positioned on the face to assistin imparting spin. The top line is generally configured to have aparticular look to the golfer and to provide weight. The sole of thegolf club is particularly important to the golf shot because it contactsand interacts with the ground during the golf shot. The sole of the golfclub is of particular importance for wedges, i.e., clubs used forshorter shots. Wedges generally have a loft of between 45° and 60°, butcan be greater.

[0003] Prior golf clubs have included a variety of flange or soleconfigurations. As stated above, the sole interfaces with the ground.Thus, there are many sole configurations to optimize the performance ofthe club. Typically, the sole of the club is slightly curved such thatwhen the club is placed on the ground, the leading edge is located abovethe ground and the trailing edge is located above the ground. Thecurvature toward the front of the club generally provides bounce. Bounceassists in preventing the club from digging into the ground andsubstantially slow the club head speed. The curvature toward thetrailing edge generally prevents the club head from getting caught onthe ground during the back swing.

[0004] There is typically more bounce built into wedges because ofvarious reasons. First, wedges are generally swung at a steeper inclinetoward the ground and, therefore, more likely to dig into the ground.Second, wedges generally see different types of ground conditions,including sand, rough and hard pan surfaces. Thus, the sole of thewedge-type golf club is critical to the clubs playability andperformance.

[0005] The present invention is directed to an improved golf club solefor an iron-type golf club that increases the club's playability. Theinvention is particularly useful on wedges.

SUMMARY OF THE INVENTION

[0006] The present invention is directed to a golf club having a solethat includes a bottom surface that is substantially planar with theground when addressed by a player. The bottom surface is preferablycrescent-shaped with a back border being substantially straight andbeing adjacent to the tailing edge of the sole and a front borderextending toward the leading edge of the club. Preferably, the furthestforward point of the front border is near the middle of the sole betweenthe toe and the heel.

[0007] The present invention also comprises a golf club having a solecomprising four (4) surfaces: a positive bounce crescent surface; abottom crescent surface and heel and toe sole surfaces. The positivebounce crescent surface is a crescent-shaped surface adjacent to theleading edge of the club face or striking surface. The positive bouncecrescent surface is a substantially planar surface that is angled fromthe ground by a positive bounce angle. The positive bounce angle is theangle with the horizontal plane and is preferably between 16° and 30°and, more preferably, between about 10° and 20°. However, the positivebounce angle can be varied based on the player's desires. Generally, itis preferred that this angle increase for the amount of loft in theclub, i.e., the greater the angle of the striking face from vertical,the larger the positive bounce angle. However, many players have aparticular amount of bounce angle that they prefer. Thus, the bounceangle can be and often is varied to meet a particular playerspreference. The crescent has two borders; a front border approximate theleading edge of the club face and a rear border separating the crescentsurface from the other surfaces. Preferably, the front border issubstantially straight and parallel to the leading edge of the club faceand the rear border is curved such that the widest point of the crescentsurface is near the center of the club between the toe and heel.

[0008] The second surface is the bottom crescent surface which is also asubstantially flat surface and is substantially planar with the groundwhen the club is addressed by the golfer. The bottom crescent surfacewill generally be a flat surface having an angle with the horizontalplane of between −4° and +4° and, more preferably, between −2° and +2°when the shaft is in the vertical plane. The angle with the horizontalplane is most preferably 0°, so that the surface lies flat on the groundto stabilize the club head, but can be varied slightly for particularplayers needs. The bottom crescent surface is also preferablycrescent-shaped. The surface has two borders, a substantially straightback border nearer or at the tailing edge of the club and a curved frontborder extending toward the front of the club such that the widest pointof the crescent is near the center of the club between the toe and heel.

[0009] The furthest forward point of the bottom crescent surface and thefurthest back point of the positive bounce crescent surface abut or verynearly abut to form the primary point. This primary point is preferablylocated at a position such that the flat surface is pushed into theground when the ball is struck. Preferably, this position is verticallybelow the intersection of the plane that passes through the leading edgeand the perpendicular line though the face approximately 0.55 inchesfrom the leading edge. While the leading point can be located to adjustfor a particular player's needs, the line perpendicular to the face at0.55 inches from the leading edge preferably extends through the bottomcrescent surface.

[0010] The back border of the bottom crescent surface is generallylocated at the trailing edge of the sole. Preferably, the back border islocated at a point on the club such that the line through the backborder and perpendicular to the front face extends through the frontface more that 0.55 inches from the leading edge. Also, the back borderis preferably located more that 0.25 inches from the primary point onthe sole and, more preferably, more than 0.3 inches from the primarypoint.

[0011] The present invention is also directed to a set of irons andpreferably wedge irons having lofts greater than 45°. In a preferredset, each of the wedges has a primary point that is located very nearlybelow the intersection of the plane having the leading edge and lineperpendicular to the front face that is 0.55 inches from the leadingedge. In another preferred set of wedge irons, the back border of eachwedge is located at a point that is approximately 0.7 inchesperpendicularly from the leading edge. In another preferred set, theleading edge height is constant. In yet another preferred set, thebounce angle is constant.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a cross-sectional view of a prior art golf club having asubstantially flat sole;

[0013]FIG. 2 is a cross-sectional view of a prior art golf club having asubstantially rounded sole;

[0014]FIG. 3 is a cross-sectional view of a prior art golf club having asubstantially flat, crescent-shaped surface; FIG. 4 is a front plan viewof a golf club having a sole according to the present invention;

[0015]FIG. 5 is a bottom view of the golf club in FIG. 4;

[0016]FIG. 6 is a cross-sectional of the golf club in FIG. 4;

[0017]FIG. 7 is a bottom view of a second embodiment of a golf clubhaving a sole according to the present invention;

[0018]FIG. 8 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0019]FIG. 9 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0020]FIG. 10 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0021]FIG. 11 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0022]FIG. 12 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0023]FIG. 13 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0024]FIG. 14 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0025]FIG. 15 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0026]FIG. 16 is a blown up cross-sectional view of a portion of anotherembodiment of a sole according to the present invention;

[0027]FIG. 17 is cross-sectional view of an embodiment of a golfclub-having a sole according to the present invention;

[0028]FIG. 18 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0029]FIG. 20 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0030]FIG. 21 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0031]FIG. 22 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention;

[0032]FIG. 23 is cross-sectional view of an embodiment of a golf clubhaving a sole according to the present invention; and

[0033]FIG. 24 is a blown up cross-sectional view of another embodimentof a golf club having a sole according to the present invention.

DESCRIPTION OF THE PRIOR ART

[0034] FIGS. 1-3 represent several prior art sole configurations usedparticularly on wedges. FIG. 1 discloses a club head 1 having a frontface 2, a back face 3, a hosel 4 and a sole 5. In this embodiment, thesole 5 is a substantially flat surface. When the hosel is in thevertical plane as shown here, the sole is angled from the ground orhorizontal plane by a bounce angle Θ. The sole 5 has a leading edge LE,a trailing edge TE and a contact point CP. As shown, in this embodiment,the contact point CP is at the trailing edge TE. When the club 1 isaddressed, the leading edge LE is above the ground by a leading edgeheight LEH and the club hits the ground at the contact point PC, whichis spaced from the leading edge by a distance d_(c).

[0035] Referring now to FIG. 2, the club head 1 has a front face 2, aback face 3, a hosel 4 and a sole 5. In this embodiment, the sole 5 is arounded surface. When the hosel is in the vertical plane as shown, thesole 5 is angled from the ground or horizontal plane by a bounce angleΘ. In this embodiment, the leading edge LE is above the ground by aboutthe same leading edge height LEH as the club in FIG. 1, but the contactpoint CP is much closer to the leading edge LE. That is, the distance dcto the contact point CP is reduced.

[0036]FIG. 3 is from U.S. Pat. No. 5,549,296, which is incorporated byreference herein. The sole S has a positive bounce surface 110 near theleading edge LE of the club, a trailing sole surface 112 and a crescentsurface 111 between the positive bounce surface 110 and the trailingsole surface 112 adjacent the trailing edge TE. The crescent surface 111and the positive bounce surface 110 both have positive bounce angles Θ₁and Θ₂, respectively, such that the leading edge LE is above the groundby a leading edge height LEH. The trailing sole surface 112 has anegative relief angle. Although not evident in this figure, the crescentsurface has a generally straight front boundary and a curved rearboundary that forms the contact point CP of the club.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0037] Referring to FIGS. 4-6, the present invention is directed to agolf club 10 having front face 11, a heel 12, a toe 13, a hosel 14, asole 15 and a back face 16. The sole 15 includes a bottom surface 17that is substantially planar with the ground when addressed by a player.That is, when the player addresses the club to the ball and the hosel issubstantially in the vertical plane and at the proper lie angle as shownin FIGS. 6 and 4 respectively, the bottom surface 17 is substantiallyplanar with the ground. For standard clubs, this bottom surface 17should be substantially planar or flat and approximately or actuallyperpendicular to a vertical line through the surface. However, forcustom clubs, the bottom surface 17 may be angled according to the way aplayer addresses the ball. Thus, when the hosel 14 is in the verticalplane, the bottom surface 17 is preferably angled between −4° and +4°and, more preferably, between −2° and +2°. Most preferably, the bottomsurface 17 is substantially in the horizontal plane when addressed bythe player to be flush with the ground.

[0038] The bottom surface 17 is preferably crescent-shaped with a backborder 18 being substantially straight and being adjacent to the tailingedge TE of the sole and a front border 19 extending toward the leadingedge LE of the club 10. Preferably, the furthest forward point, orprimary point PP, of the front border 19 is near or substantially in themiddle of the sole 15 between the toe 13 and the heel 12.

[0039] In the most preferred embodiment of the present invention, thegolf club 10 is comprised of a sole comprising four (4) surfaces: apositive bounce crescent surface 20, the bottom crescent surface 17 andheel and toe surfaces 21 and 22 respectively.

[0040] The positive bounce crescent surface 20 is a crescent-shapedsurface adjacent to the leading edge LE of the club face or strikingsurface 11. The positive bounce crescent surface 20 is a substantiallyplanar surface or surface with a slight concave or convex curvature fromfront to back that is angled from the ground by a positive bounce angleΘ. The positive bounce angle is the angle with the horizontal plane orground and is preferably between 10° and 20°. However, the positivebounce angle 0 can be varied based on the player's desires. Generally,it is preferred that this angle increase for the amount of loft in theclub, i.e., the greater the angle of the striking face from vertical,the larger the positive bounce angle. However, many players have aparticular amount of bounce angle that they prefer. Thus, the bounceangle Θ can be and often is varied to meet a particular playerspreference.

[0041] The positive bounce crescent surface 20 has a front border 23that is approximate the leading edge LE of the club face and a rearborder 24 separating the positive bounce crescent surface 20 from theother surfaces 17, 21 and 22. Preferably, the front border 23 issubstantially straight and approximately parallel with the leading edgeLE of the club face and the rear border 24 is curved such that thewidest point of the crescent surface is near the center of the club sole15 between the toe 13 and heel 12.

[0042] The furthest forward point, or primary point PP, of the bottomcrescent surface 17 and the furthest back point of the positive bouncecrescent surface 20 abut or very nearly abut at the primary point PP.This primary point PP is preferably located a distance X from theleading edge LE such that when the ball is impacted the bottom surfaceis forced into the ground. Preferably, this location is at a positionthat is vertically below the intersection of the leading edge plane LEPthat passes through the leading edge LE and the perpendicular line PLthough the face at approximately 0.55 inches from the leading edge LE orat the 4^(th) score line. While the primary point PP can be located toadjust for a particular player's needs, the perpendicular line PL to theface at 0.55 from the leading edge inches or at the 4^(th) score linepreferably extends through the bottom crescent surface 17 for higherlofted clubs. Generally, the distance X is greater than about 0.5 inchesand, more preferably, the distance X is between about 0.55 and 0.8inches.

[0043] The back border 18 of the bottom crescent surface 17 is generallylocated at or very near the trailing edge TE of the sole. Preferably,the back border 18 is located at a point on the club sole 15 such thatthe line through the back border and perpendicular to the front faceextends through the front face more than 0.55 inches from the leadingedge or behind the 4^(th) score line. Also, the back border 18 ispreferably located a distance Y more that about 0.25 inches from theprimary point PP on the sole 15 and, more preferably, more than about0.3 inches from the primary point PP.

[0044] The bottom crescent surface 17 and the positive bounce surface 20also separate the toe surface 22 from the heel surface 21. Thesesurfaces preferably curve upwardly from the center to provide a verticalrelief in the heel 12 and toe 13 such that there is little groundpressure away from the bottom crescent surface 17. Such relief meansthat the ends of the contact area along the front border 19 of thebottom crescent surface 17 are the lowest points of the heel and toesurfaces 21 and 22.

[0045] Referring to FIG. 7, the golf club 10 is similar to the flat soleclub shown in FIG. 1, but includes a bottom crescent surface 11. Thus,the cross-sectional view of this club 10 is substantially the same asFIG. 6 and all of the discussion about the first embodiment shown inFIGS. 4-6, regarding the front border 19, the rear border 18 and thepositioning of the primary point PP apply to this embodiment.

[0046] The present invention is also directed to a set of irons andpreferably wedge-type irons having lofts greater than 45°. In apreferred set, as shown in FIGS. 8-11 and as set forth in Table I, eachof the wedges has sole 15 configured such as that shown in FIGS. 4-7.Each of the club heads in this set has a primary point PP that islocated at or substantially below the intersection of the plane throughthe leading edge LEP and line perpendicular to the front face that is0.55 inches from the leading edge or at the 4^(th) score line. Further,each of the wedge-type irons has a maximum width of-the bottom crescentsurface d₁ that is substantially the same and that is greater than about0.3 inches. Also, the maximum width of the bottom crescent surface d₁ isgreater than 0.2 times the total sole width d₂. In this embodiment, theleading edge height LEH is substantially constant through the set and isless than 0.25 inches. The bounce angle Θ for each of the clubs isbetween 12° and 15° and increases through the set with an increase iniron loft. Finally, the perpendicular distance between the trailing edgeand the front face d₃ is less than 1.0 inches for each of the irons inthe set and preferably decreases with the iron loft through the set. Ineach of the irons in this set, the line perpendicular to the face at0.55 inches from the leading edge or at the 4^(th) score line extendsthrough the bottom crescent surface 17. TABLE I Fig. Loft d₁ d₂ d₃ Θ LEH8 54° .31″ 1.04″ .80″ 13.2° .22″ 9 56° .31″ 1.03″ .78″ 13.3° .22″ 10 58°.31″ 1.01″ .75″ 13.3° .22″ 11 60° .31″ 1.00″ .70″ 14.0° .22″

[0047] Referring to Table II and FIGS. 12-15, disclose another preferredset of wedge irons includes a trailing edge TE, each wedge located at adistance d₃ that is approximately 0.7 inches perpendicularly from theleading edge. In this set, the maximum width d₁ of the bottom crescentsurface 17 is substantially constant throughout the set and is greaterthan about 0.25 inches. Moreover, the maximum width of the bottomcrescent surface d₁ is greater than 0.3 times the maximum width of thesole d₂. In this set, the bounce angle Θ decrease with the loft of theclub and preferably ranges between about 13° and about 20°. As with theprevious set, the leading edge height LEH is substantially constant andis less than about 0.25 inches. TABLE II Fig. Loft d₁ d₂ d₃ Θ LEH 12 54°.31″ .87″ .7″ 18.2° 22″ 13 56° .31″ .90″ .7″ 17.3° .22″ 14 58° .31″ .94″.7″ 16.0° .22″ 15 60° .31″ .99″ .7″ 14.0° .22″

[0048] Referring now to Table III and FIGS. 16-19, another preferred setof wedge irons have a maximum width d₁ of the bottom crescent surface 17that increases with the loft of each club. The maximum width d₁ of thebottom crescent surface 17 of each club is greater than 0.3 inches andis preferably between about 0.3 and 0.5 inches. Moreover, the maximumwidth d₁ of the bottom crescent surface 17 is approximately ½ of thedistance between the front face and the trailing edge d₃ or greater. Thedistance between the front face and the trailing edge d₃ issubstantially constant. The bounce angle Θ is preferably between 12° and15° and the leading edge height LEH is substantially constant at aheight of less than about 0.25 inches. Preferably, the maximum width d₁of the bottom crescent surface 17 is greater than the leading edgeheight LEH. TABLE III Fig. Loft d₁ d₃ Θ LEH 16 54° .33″ .75″ 14.0° .22″17 56° .36″ .75″ 13.2° .22″ 18 58° .38″ .75″ 13.3° .22″ 19 60° .41″ .75″13.0° .22″

[0049] Referring now to Table IV and FIGS. 20-23, another preferred setof wedge irons have a substantially constant bounce angle Θ. Preferably,the bounce angle Θ is between about 12° and 20°. More preferably, thebounce angle Θ is between about 12° and 15°. Also, it is preferred thatthe distance from the front face to the trailing edge d₃ remainsubstantially constant and between about 0.5 inches and 1 inch. Mostpreferably, the bottom crescent surface maximum width d₁ is changed andthe leading edge height LEH is changed to maintain a constant bounceangle Θ and distance from the front face to the trailing edge d₃.However, it is preferred that the leading edge height LEH is less thanabout 0.25 inches for each club and that the bottom crescent surfacemaximum width d₁ is greater than about 0.25 inches. TABLE IV Fig. Loftd₁ d₃ Θ LEH 20 54° .33″ .75″ 14.0° .22″ 21 56° .33″ .75″ 14.0° .23″ 2258° .36″ .75″ 14.0° .24″ 23 60° .40″ .75″ 14.0° 24″

[0050] It will be understood that each of the clubs disclosed in TablesI-IV and FIGS. 8-28 above are representative of individual clubsaccording to the present invention and that the clubs could be combinedwith other clubs to form additional sets. Based on the teachings hereinand a player's preference, one of ordinary skill can create manydifferent clubs or sets that are within the scope of the invention.Thus, the above disclosure of sets is merely meant to provide examplesof preferred embodiments and not limit the scope of the claims below.Furthermore, while each of the sets above include four irons, it isintended that the word set mean two or more clubs. Also, the setsdiscussed above are for wedge-type irons, however, it is clear that theteachings herein can be applied to a full set of irons such as thosetaught in U.S. Pat. No. 5,549,296.

[0051] Referring to FIG. 24, another preferred embodiment of theinvention can include a camber positive bounce surface 20 that has aconvex curvature radius R. Most preferably, the radius of the curvatureR of the positive bounce surface 20 is greater than about 1 inch and,more preferably is between about 1.5 inches and 2.5 inches. The radius Rof the curvature of the positive bounce surface of the club shown inFIG. 24 is about 2 inches. The radius of the curvature R is alsopreferably more than twice the distance between the front face and thetrailing edge d₃ (as shown in FIGS. 8-23) and more than four times themaximum width of the bottom crescent surface d₁ Each of the club headsset forth above can include this camber positive bounce surface 20 aswell as a concave curvature of similar radius.

We claim:
 1. A golf club having a sole comprising a bottom surface thatis substantially planar with the ground when addressed by a player, thebottom surface being crescent-shaped with a back border beingsubstantially straight and being substantially adjacent to a tailingedge of the sole and a front border extending toward the leading edge ofthe club.
 2. The golf club of claim 1, wherein the bottom surfaceincludes a furthest forward point positioned near a middle of the solebetween a toe and a heel of the club.
 3. The golf club of claim 2,wherein the distance between the forward most point and the back borderis greater than about 0.25 inches.
 4. The golf club of claim 1 furthercomprising a positive bounce crescent surface positioned between thebottom crescent surface and a leading edge of the sole and heel and toesole surfaces.
 5. The golf club of claim 4 wherein the positive bouncecrescent surface is a crescent-shaped surface adjacent to the lower edgeof the sole.
 6. The golf club of claim 5 wherein the positive bouncecrescent surface is a substantially planar surface that is angled fromthe ground by a positive bounce angle.
 7. The golf club of claim 6,wherein the positive bounce angle is between 6° and 30°.
 8. The golfclub of claim 5, wherein the positive bounce crescent surface has twoborders, a front border located approximate the leading edge of the soleand a rear border separating the crescent surface from the othersurfaces.
 9. The golf club of claim 8, wherein the front border issubstantially straight and parallel to the leading edge of the sole andthe rear border is curved such that the widest point of the positivebounce crescent surface is near the middle of the sole between the toeand heel.
 10. The golf club of claim 1, wherein the bottom crescentsurface is a substantially flat surface having an angle with thehorizontal plane of between −4° and +4° when the shaft is in thevertical plane.
 11. The golf club of claim 1, wherein the bottomcrescent surface is a substantially flat surface having an angle withthe horizontal plane of between −2° and +2° when the shaft is in thevertical plane.
 12. The golf club of claim 8, wherein a furthest forwardpoint of the bottom crescent surface and a furthest back point of thepositive bounce crescent surface are substantially adjacent to form aprimary point.
 13. The golf club of claim 1, wherein the club has a loftof greater than about 45° and a primary point located at a position thatis vertically below an intersection of a plane that passes through theleading edge and a perpendicular line though the face approximately 0.55inches from the leading edge in the middle of the club between the heeland toe.
 14. The golf club of claim 8, wherein a line perpendicular tothe face at 0.55 inches from the leading edge extends through the bottomcrescent surface.
 15. A set of golf clubs having a sole comprising abottom surface that is substantially planar with the ground whenaddressed by a player, the bottom surface being crescent-shaped with aback border being substantially straight and being substantiallyadjacent to a tailing edge of the sole and a front border extendingtoward the leading edge of the club.
 16. The set of golf clubs of claim15, wherein the set is comprised of irons having lofts of greater than46.
 17. The set of golf clubs of claim 15, wherein each of the golfclubs has a primary point being the most forward point on the frontborder that is located substantially below an intersection of ahorizontal plane through the leading edge and a line perpendicular tothe front face approximately 0.55 inches from the leading edge.
 18. Theset of golf clubs of claim 15, wherein each of the golf clubs has aprimary point being the most forward point on the front border that islocated substantially below an intersection of a horizontal planethrough the leading edge and a line perpendicular to the front face at a4^(th) score line thereon.
 19. The set of golf clubs of claim 15,wherein each of the bottom crescent surfaces has a maximum width that isgreater than about 0.3 inches.
 20. The set of golf clubs of claim 15,wherein each of the bottom crescent surfaces has a maximum width that issubstantially the same as the others.
 21. The set of golf clubs of claim15, wherein each of the bottom crescent surfaces has a maximum widththat is greater than 0.2 times a total sole width.
 22. The set of golfclubs of claim 15, wherein each of the clubs has a leading edge heightthat is substantially constant through the set.
 23. The set of golfclubs of claim 15, wherein each of the clubs has a leading edge heightthat is less than 0.25 inches.
 24. The set of golf clubs of claim 15,wherein each of the clubs has a bounce angle between about 12° and 15°.25. The set of golf clubs of claim 15, wherein each of the clubs has abounce angle that increases through the set with an increase in ironloft.
 26. The set of golf clubs of claim 15, wherein each of the clubsis configured such that a line perpendicular to the face at 0.55 inchesfrom the leading edge extends through the bottom crescent surface 17.27. The set of golf clubs of claim 15, wherein each of the back bordersis located approximately 0.7 inches perpendicularly from the leadingedge.
 28. The set of golf clubs of claim 15, wherein each of the clubshas a bounce angle that decrease with the loft of the club through theset.
 29. The set of golf clubs of claim 15, wherein each of the clubshas a maximum width of the bottom crescent surface that increases withthe loft of each club through the set.
 30. The set of golf clubs ofclaim 15, wherein each of the clubs has a maximum width of the bottomcrescent surface that is approximately ½ of a distance between the frontface and the trailing edge or greater.
 31. The set of golf clubs ofclaim 30, wherein the distance between the front face and the trailingedge is substantially constant through the set.
 32. The set of golfclubs of claim 15, wherein each of the clubs has a maximum width of thebottom crescent surface that is greater than a leading edge height foreach club.
 33. The set of golf clubs of claim 15, wherein each of theclubs has a substantially constant bounce angle.
 34. The set of golfclubs of claim 15, wherein each of the clubs has a distance measuredperpendicularly from the front face to the trailing edge that issubstantially constant through the set.
 35. The set of golf clubs ofclaim 34, wherein distance measured perpendicularly from the front faceto the trailing edge is between about 0.5 inches and 1 inch.
 36. A golfclub having a sole comprising a leading edge, a positive bounce surfacesubstantially adjacent to the leading edge, a trailing edge and a bottomsurface that is substantially planar with the ground when addressed by aplayer and adjacent the trailing edge.
 37. The golf club of claim 36,wherein the bottom surface is crescent-shaped and has a back borderbeing substantially straight that is substantially adjacent to thetailing edge and a front border extending toward the positive bouncesurface of the club.
 38. The golf club of claim 36, wherein the positivebounce surface has a convex curvature radius R.
 39. The golf club ofclaim 36, wherein the radius of the positive bounce surface is greaterthan about 1 inch.
 40. The golf club of claim 36, wherein the radius ofthe positive bounce surface is more than twice a perpendicular distancebetween the front face and the trailing edge.
 41. The golf club of claim36, wherein the radius of the positive bounce surface is more than fourtimes a maximum width of the bottom surface.
 42. The golf club of claim36, wherein the club has a loft angle of greater than about 45°.